1. Field of Invention
This disclosure relates in general to oil and gas equipment, and in particular to a method of measuring flow to determine if hydraulic controls have acted to carry out a specific function. In particular, the disclosure provides systems and methods to monitor aggregated flow rates and pressures in hydraulic control systems to realize information about a specific load of interest.
2. Related Technology
Blowout preventer (BOP) systems are hydraulically-controlled systems used to prevent blowouts from subsea oil and gas wells. Subsea BOP equipment typically includes a set of two or more redundant control systems with separate hydraulic pathways to operate a specified BOP function on a BOP stack. The redundant control systems are commonly referred to as blue and yellow control pods. In known systems, a communications and power cable sends information and electrical power to an actuator with a specific address. The actuator in turn moves a hydraulic valve, thereby opening a fluid path to a series of other valves/piping to control a portion of the BOP.
One deficiency with current BOP systems is that hydraulic fluid communication from the surface is made through a pair of redundant conduits with fluid supplied from a single source with limited measuring means, oftentimes a single flow meter. When there are multiple, separate control systems at the sea surface utilizing a common hydraulic supply to feed subsea components, the multiple, separate control systems on the surface may not accurately realize what functions have been carried out by another control system based on a common measurement device, such as a common flow meter or common pressure meter. For example, a primary surface control system used to execute functions by feeding hydraulics to subsea components may not accurately convey to a backup safety system the executed functions when the systems have a common flow meter.
In known systems, measuring the fluid going to a specific load is difficult when the system has two or more independent control systems which are utilizing a single hydraulic source. Adding additional flow meters and pressure meters can complicate systems and introduce other deficiencies.